By the way, GateIn 3.2.0-CR01 was released yesterday, and FINAL will be released in three weeks.

Mabye I should wait to try again till the FINAL version is out.

AFAIK, you don't waste time on trying that, because the problem doesn't come from GateIn, it's SSO problem, you should follow activities on the SSO project instead of in JIRA. Or you can checkout the code from source code

There are several major changes which relate to GateIn and SSO integration such as request handler, authentication... in a short time, I guess that you're using an old version of GateIn and SSO. Please do these steps with latest version of GateIn and SSO, and let us know if everything work well.